Alittle Airsal advise please..piston on backwards?

Just rebuilt my motor today. Granted it's my fisrt time. Got it back together, Airsal 65cc, stock carb, #66 jet, tecno estroil pipe. When I started it up it runs but won't idle. Sounds loud...clacky...and alot of fuel mist is blowing back out of the carb through the airfilter. Double checked the reed valve and everything seemed okay there. Now the big question...does it sound like I put the piston on backwards? And, if so, have I f--ked anything up by running it abit? And which way is forward? Thanks.

Re: Alittle Airsal advise please..piston on backwa

James Foster /

I'm no expert at tomos ped's, and It's fine for a little mist to come back out the carb, but if it's a lot of it, the extra fuel coming out the carb might mean you're running a little rich. As for the noises, does it sound like a dinging sound, or is it an all out knocking? And from my experience, if you accidentally put the piston in upside down, it usually reduces output quite a bit. You might want to make sure carburation is sound as well before moving on.

Hope this helps,

JF

Re: Alittle Airsal advise please..piston on backwa

are you sure you have installed the piston rings proper like?

ther is tiny little pins in the grooves of the piston that you have to line up with the gaps in the rings.

just a thought.Also look for a arrow or mark on your piston, that should be at the bottom when you install it.

Re: Alittle Airsal advise please..piston on backwa

The rings are in okay. What I need to know is do the holes in the piston (the two side by side oblong ones) go on the reed valve side or the exhaust side of the cylinder? My guess was they line up on the exhaust side. Stupid of me not to check before I took the old piston off, but I was to busy concerning myself with rings and clips.

Re: Alittle Airsal advise please..piston on backwa

The side of the piston with the hole or holes is the intake side. Your problem sounds to me like the reed valves are not sealing closed properly. Look real close at the reeds and gaskets and make sure the gasket is not making the reeds hang up.I installed an airsal kit not long ago and the reed gasket was right against the reed flap so I trimmed the gasket alittle.

Re: Alittle Airsal advise please..piston on backwa

John Joedicke /

Definitely dual holes in piston are on the intake /reeds side

Re: Alittle Airsal advise please..piston on backwa

Don Pflueger /

intake side. they are ports for the reed to aspirate the crankcase.

Re: Alittle Airsal advise please..piston on backwa

Intake side...daa. Yeah I finally got an intake vision and it all made sense. I haven't checked yet...but I'm sure that's it. That would explain the Windex-like mist spraying back out of the carb. But change the pinclips?! Is that really necessary? They say they are only made to be compressed once...but I know lots who disagree. Anyone got any horror stories of a cousin who recompressed his ring clips once? Ended up a road burger sandwich?

Re: Alittle Airsal advise please..piston on backwa

Don Pflueger /

ive reused them thousands of times. put them in tho so that they are compressed from side to side and not up and down. the reason is that inertia at high rpm can cause them to compress and then come out.

Re: Alittle Airsal advise please..piston on backwa

Do you mean so as the piston travels up and down they get compressed on the arch by the inertia...like a U and not on the sides...like a C?

Re: Alittle Airsal advise please..piston on backwa

Don Pflueger /

install them like a U

Re: Alittle Airsal advise please..piston on backwa

Thanks. So yeah I had the piston on backward. In and out in 15 minutes and all is well. Sometimes you pay alittle to much attention to the details...while missing the big picture. All in all a good lesson. Thanks everyone, Donp, I'll try not to do to many wheelies...LCG taking it into the trees in that video made me realize how silly I'd look anyway.

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